Topic 9: Bones, joints and muscles of the thoracic cage Flashcards
(94 cards)
1
Q
How many pairs of ribs are there?
A
12
2
Q
How many true ribs are there?
A
7
3
Q
how many false ribs are there?
A
3
4
Q
how many floating ribs are there?
A
2
5
Q
What are the 3 parts of the sternum?
A
- manubrium
- body
- xiphoid
6
Q
How many thoracic vertebrae?
A
12
7
Q
what else makes up the bones of the thorax?
A
costal cartilages
8
Q
What are the boundaries for the thoracic inlet?
A
Rib 1, T1, Manubrium, costal cartilages
9
Q
What are the boundaries for the thoracic outlet?
A
inferior
costal cartilages, lower 3-4 thoracic vertebrae
10
Q
What are the 2 joints of the sternum?
A
- manubriosternal
- xiphisternal
11
Q
What are the 2 joints of the anterior ribs?
A
- sternocostal (1st & 2-7)
- costochondral
* chondral = ribs
12
Q
What are the 2 joints of the posterior ribs?
A
- costovertebral
- costotransverse
13
Q
Classify the Manubriosternal joint
A
secondary cartilaginous- symphysis
14
Q
how moveable is the manubriosternal joint?
A
slightly
15
Q
classify the xiphisternal joint
A
secondary cartilaginous- symphysis
16
Q
How moveable is the 1st sternocostal joint?
A
immovable (lots of imp structures around there)
17
Q
how moveable is the xiphisternal joint?
A
slightly moveable but ossifies in middle age
18
Q
Classify the 1st sternocostal joint
A
primary cartilaginous- synchondrosis
19
Q
Classify the 2nd-7th sternocostal joints
A
synovial, multi-axial, plane
20
Q
How moveable are the 2nd-7th sternocostal joints?
A
small range of twist & glide (for breathing)
21
Q
Classify the costochondral joints
A
primary cartilaginous - synchondrosis
22
Q
How moveable are the costochondral joints?
A
immovable
23
Q
Classify the interchondral joints
A
synovial, multiaxial, plane (except 9&10- fibrous)
24
Q
Which ribs have interchondral joints?
A
ribs 6-10
25
explain where the interchondral joints lie
between borders of costal cartilages of ribs 6-10 and lower border of cartilage above
26
What are the 3 bony landmarks on the ribs which articulate with the vertebrae?
1. head
2. neck
3. tubercle
27
What bony landmark on the vertebrae does the head of the rib articulate with?
demi facets
28
What bony landmark on the vertebrae does the tubercle of the rib articulate with?
transverse processes
29
Classify the costovertebral joint
synovial, multi-axial, plane
30
What movements are allowed at the costovertebral joint?
small range of twist and glide
31
Classify the costotransverse joint
synovial, multi-axial, plane
32
what movements are facilitated at the costotransverse joint?
small range of twist and glide
33
articular surfaces of the costovertebral joints
1. head of rib
2. (demi) facet on the body of the thoracic vertebra
34
What thoracic vertebra does rib 1 articulate with in the costovertebral joints?
T1
35
Which thoracic vertebrae does rib 2 articulate with in the costovertebral joints?
T1 and T2
36
Which thoracic vertebrae does rib 9 articulate with in the costovertebral joints?
T8 & T9
37
Which thoracic vertebra does rib 10 articulate with in the costovertebral joints?
T10
38
Which thoracic vertebra does rib 11 articulate with in the costovertebral joints?
T11
39
Which thoracic vertebra does rib 12 articulate with in the costovertebral joints?
T12
40
Costotransverse joints- articular surfaces
1. tubercle of rib
2. facet on the transverse process of the thoracic vertebra
41
Which ribs have no costotransverse jt and why?
ribs 11 &12 - no costal cartilage and transverse process articulation (floating)
42
What are the 2 ligaments of the costovertebral joints?
1. radiate
2. intra-articular
43
What are the 3 ligaments of the costotransverse joints?
1. costotransverse
2. lateral costotransverse
3. superior costotransverse
44
COSTOVERTEBRAL LIGAMENTS
Where does the radiate ligament span?
From the head of the rib -- to the body of the vertebra above, the vertebra of the same number and the intervening IV disc
45
Function of the radiate ligament
- limit movement in all directions
- attaches head of rib to vert
46
Intra-articular ligament
Where does it go?
From the head of the rib-- to the IV disc, divides the cavity into 2
47
Function of the intra-articular ligament
keeps head of rib in place
48
COSTOTRANSVERSE JT LIGAMENTS
1. superior costotransverse ligament
Where does it go?
From the neck of the rib to the transverse processes of the vertebra above
49
What is the function of the superior costotransverse ligament
limits separation of the ribs
50
2. lateral costotransverse ligament
Where does it go?
strong band between tip of transverse processes and the costal tubercle (same level)
51
Function of the lateral costotransverse ligament
keeps rib & thoracic vert together
52
3. costotransverse ligament
Length of fibres
short fibres
53
where does the costotransverse ligament go?
from the back of the neck of the rib -- to the front of the transverse process
54
DIAMETERS OF THE THORAX
What happens to ALL dimensions of the thoracic cage (TC) with each inspiration?
increase
55
DIAMETERS OF THE THORAX
What happens to the vertical diameter of the TC with each inspiration and how?
Increased by descent of diaphragm
56
DIAMETERS OF THE THORAX
What happens to the antero-posterior diameter with each inspiration and how?
increased by movement of the sternum and anterior parts of ribs
57
DIAMETERS OF THE THORAX
What happens to the lateral diameter with each inspiration and how?
increased by movements of the lateral parts of the ribs
58
What are the 2 mechanisms for movement of the ribs?
1. pump handle
2. bucket handle
59
Which ribs does the pump handle mechanism involve?
upper ribs 2-5
60
What axis diameter does pump handle mechanism increase?
AP diameter
61
What is the movement axis for pump handle mechanism?
along neck of rib
62
Which ribs does the bucket handle mechanism involve?
lower ribs 8-10
63
Where does the diameter increases in the bucket handle mechanism?
lateral
64
what is the movement axis for the bucket handle mechanism?
through the costovertebral and sternocostal joints
65
MUSCLES OF THE THORACIC CAGE:
1. diaphragm
What does it cover?
the thoracic outlet
66
Attachments of the diaphragm
1. bodies & intervening discs L1-L3
2. inner surface of the ribs 7-12 and their costal cartilages (lat &ant)
3. posterior surface of the xiphoid process of the sternum
4. central tendon
67
what is the prime role of the diaphragm
prime mover for inspiration
68
What 2 areas does the diaphragm separate?
the thorax & abdo
69
What happens to the thoracic cage when the diaphragm contracts?
1. increase volume
2. decrease pressure
70
What happens to the abdo when the diaphragm contracts?
1. decrease volume
2. increase pressure
71
What are the 3 apertures of the diaphragm?
1. Abdominal aorta (T12)
2. Oesophagus (T10)
3. Inferior Vena Cava (T8)
72
Where is the abdominal aorta aperture of the diaphragm located?
behind the diaphragm
73
Is the abdominal aorta aperture affected by diaphragm contraction?
no
74
Where is the oesophagus aperture located?
through the muscle of the diaphragm
75
what happens to the oesophagus aperture when diaphragm contracts?
closed
76
Where is the inferior vena cava aperture located?
through the central tendon
77
What happens to the inferior vena cava aperture when diaphragm contracts?
opens
78
OTHER MUSCLES OF THORAX
1. intercostals
where do they go?
from the lower border of one rib to the upper border of the rib below
79
Three layers of intercostals:
1. external
2. internal
3. innermost
80
Role of the intercostals
1. stiffen the space between the ribs
2. role in breathing & in posture
81
direction of external intercostal fibres?
hands in pockets
82
direction of innermost & internal intercostal fibres?
opposite to hands in pockets
83
What is an accessory muscle of inspiration?
any muscle attaching to the ribs from above can lift the ribs and increase thoracic volume (inspiration)
84
e.g. of inspiratory muscles (upper limb)
serratus anterior, pec major & minor, sternocleidomastoid
85
e.g. inspiratory muscles of the vertebral column
1. scalenes group
2. serratus posterior superior
86
Are expiratory muscles largely active or passive in awake humans?
passive
87
what happens with the diaphragm at the start of expiration?
contracts eccentrically for a short period to slow expiratory rate
88
Muscles used in FORCED expiration
1. abdominal muscles
2. any other muscle that can pull the ribs down e.g. serratus posterior, QL
89
What happens to the diameter of the rib cage in forced expiration
decreases
90
4 phases of respiratory cycle
1. quiet inspiration
2. forced inspiration
3. quiet expiration
4. forced expiration
91
Muscles responsible for quiet inspiration
diaphragm, external intercostals
92
Muscles responsible for forced inspiration
diaphragm, pec maj & min, skelinis, sternoclydomastoid, serr ant, lat dorsi, ser post sup
93
Muscles responsible for quiet expiration
diaphragm -- eccentric initially -- relaxes after
94
Muscles responsible for forced expiration
abd muscles, serratus post, longissimus, lat dorsi, ext/int obliques, iliocostalis, transversus abdominus, serr post inf, QL
